1. Field of the Invention
The present invention relates to a mobile communication system, and in particular, to a system and method for service interworking between heterogeneous communication systems in a mobile communication system.
2. Description of the Related Art
Mobile communication systems are evolving into the form of a system that can provide various services, such as broadcasting, multimedia images, multimedia messages, etc. In particular, a 4th Generation mobile communication system is being developed so as to provide high-speed mobile users with data services at a data transfer rate of 100 Mbps or greater and to provide low-speed mobile users with data services at a data transfer rate of 1 Gbps or greater while departing from services centered on voice and packet data communications.
Systems approximate to the 4th Generation mobile communication system includes a portable Internet system. The portable Internet system is also called a Wireless Broadband (WiBro) communication system, and is compatible with communication systems based on IEEE (Institute of Electrical and Electronics Engineers) 801.16e.
The WiBro communication system has been commercialized or is under development for commercialization in some countries, and research is being conducted to evolve the WiBro communication system into a WiBro evolution communication system. The WiBro evolution communication system is aimed at supporting mobility up to 300 km per hour, supporting variable bandwidths, minimizing overhead, and so forth. An example of the WiBro evolution system is a communication system based on IEEE 802.16m.
The WiBro evolution communication system is intended to employ evolved technologies that have not been used in the WiBro communication system. Such evolved technologies include multiple antenna technology, IPv6 technology, multicast/broadcast service technology, and the like.
Assuming that the WiBro evolution communication system is implemented, the WiBro communication system must obviously interwork with the WiBro evolution communication system. However, the WiBro communication system and the WiBro evolution communication system may have different sub-channel structures or different signal formats. This means that the WiBro communication system and the WiBro evolution communication system are heterogeneous with respect to each other. Therefore, when the WiBro communication system and the WiBro evolution communication system coexist in a certain communication system, a specific way to solve the interworking problem between the WiBro communication system and the WiBro evolution communication system must be defined.